diff options
| author | Don Zickus <dzickus@redhat.com> | 2010-02-05 21:47:05 -0500 |
|---|---|---|
| committer | Ingo Molnar <mingo@elte.hu> | 2010-02-08 08:29:03 +0100 |
| commit | 84e478c6f1eb9c4bfa1fff2f8108e9a061b46428 (patch) | |
| tree | 15be1e0d92d4439e49ecc98a504589dc596fc211 | |
| parent | 1fb9d6ad2766a1dd70d167552988375049a97f21 (diff) | |
nmi_watchdog: Config option to enable new nmi_watchdog
These are the bits that enable the new nmi_watchdog and safely
isolate the old nmi_watchdog. Only one or the other can run,
not both at the same time.
Signed-off-by: Don Zickus <dzickus@redhat.com>
Cc: Linus Torvalds <torvalds@linux-foundation.org>
Cc: Andrew Morton <akpm@linux-foundation.org>
Cc: gorcunov@gmail.com
Cc: aris@redhat.com
Cc: peterz@infradead.org
LKML-Reference: <1265424425-31562-4-git-send-email-dzickus@redhat.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
| -rw-r--r-- | arch/x86/kernel/apic/Makefile | 7 | ||||
| -rw-r--r-- | arch/x86/kernel/traps.c | 2 | ||||
| -rw-r--r-- | include/linux/nmi.h | 4 | ||||
| -rw-r--r-- | kernel/Makefile | 1 | ||||
| -rw-r--r-- | lib/Kconfig.debug | 13 |
5 files changed, 26 insertions, 1 deletions
diff --git a/arch/x86/kernel/apic/Makefile b/arch/x86/kernel/apic/Makefile index 565c1bfc507d..1a4512e48d24 100644 --- a/arch/x86/kernel/apic/Makefile +++ b/arch/x86/kernel/apic/Makefile @@ -2,7 +2,12 @@ # Makefile for local APIC drivers and for the IO-APIC code # -obj-$(CONFIG_X86_LOCAL_APIC) += apic.o apic_noop.o probe_$(BITS).o ipi.o nmi.o +obj-$(CONFIG_X86_LOCAL_APIC) += apic.o apic_noop.o probe_$(BITS).o ipi.o +ifneq ($(CONFIG_NMI_WATCHDOG),y) +obj-$(CONFIG_X86_LOCAL_APIC) += nmi.o +endif +obj-$(CONFIG_NMI_WATCHDOG) += hw_nmi.o + obj-$(CONFIG_X86_IO_APIC) += io_apic.o obj-$(CONFIG_SMP) += ipi.o diff --git a/arch/x86/kernel/traps.c b/arch/x86/kernel/traps.c index 51ef893ffa65..973cbc4f044f 100644 --- a/arch/x86/kernel/traps.c +++ b/arch/x86/kernel/traps.c @@ -406,6 +406,7 @@ static notrace __kprobes void default_do_nmi(struct pt_regs *regs) == NOTIFY_STOP) return; +#ifndef CONFIG_NMI_WATCHDOG /* * Ok, so this is none of the documented NMI sources, * so it must be the NMI watchdog. @@ -413,6 +414,7 @@ static notrace __kprobes void default_do_nmi(struct pt_regs *regs) if (nmi_watchdog_tick(regs, reason)) return; if (!do_nmi_callback(regs, cpu)) +#endif /* !CONFIG_NMI_WATCHDOG */ unknown_nmi_error(reason, regs); #else unknown_nmi_error(reason, regs); diff --git a/include/linux/nmi.h b/include/linux/nmi.h index b752e807adde..a42ff0bef708 100644 --- a/include/linux/nmi.h +++ b/include/linux/nmi.h @@ -47,4 +47,8 @@ static inline bool trigger_all_cpu_backtrace(void) } #endif +#ifdef CONFIG_NMI_WATCHDOG +int hw_nmi_is_cpu_stuck(struct pt_regs *); +#endif + #endif diff --git a/kernel/Makefile b/kernel/Makefile index 864ff75d65f2..8a5abe53ebad 100644 --- a/kernel/Makefile +++ b/kernel/Makefile @@ -76,6 +76,7 @@ obj-$(CONFIG_AUDIT_TREE) += audit_tree.o obj-$(CONFIG_KPROBES) += kprobes.o obj-$(CONFIG_KGDB) += kgdb.o obj-$(CONFIG_DETECT_SOFTLOCKUP) += softlockup.o +obj-$(CONFIG_NMI_WATCHDOG) += nmi_watchdog.o obj-$(CONFIG_DETECT_HUNG_TASK) += hung_task.o obj-$(CONFIG_GENERIC_HARDIRQS) += irq/ obj-$(CONFIG_SECCOMP) += seccomp.o diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug index 25c3ed594c54..f80b67e72aa0 100644 --- a/lib/Kconfig.debug +++ b/lib/Kconfig.debug @@ -170,6 +170,19 @@ config DETECT_SOFTLOCKUP can be detected via the NMI-watchdog, on platforms that support it.) +config NMI_WATCHDOG + bool "Detect Hard Lockups with an NMI Watchdog" + depends on DEBUG_KERNEL && PERF_EVENTS + default y + help + Say Y here to enable the kernel to use the NMI as a watchdog + to detect hard lockups. This is useful when a cpu hangs for no + reason but can still respond to NMIs. A backtrace is displayed + for reviewing and reporting. + + The overhead should be minimal, just an extra NMI every few + seconds. + config BOOTPARAM_SOFTLOCKUP_PANIC bool "Panic (Reboot) On Soft Lockups" depends on DETECT_SOFTLOCKUP |